In order to clear the body of infecting spirochetes, phagocytic cells must be able to get hold of them. [Phagocytic cells are immune cells responsible for catching and engulfing invaders.]

In real-time phase-contrast videomicroscopy we were able to measure the speed of Borrelia burgdorferi (Bb), the Lyme spirochete, moving back and forth across a platelet to which it was tethered.

Its mean crossing speed was 1,636 microm/min (N = 28), maximum, 2800 microm/min (N = 3). This is the fastest speed recorded for a spirochete, and upward of two orders of magnitude above the speed of a human neutrophil, the fastest cell in the body. [A phagocyte.]

This alacrity and its interpretation, in an organism with bidirectional motor capacity, may well contribute to difficulties in spirochete clearance by the host.